So you want to sound like a Dalek eh? Short of going for
a quick trip to the planet Skaro there are a few things you need to keep in
mind. This article will slowly evolve into a more in depth approach to attacking
the modelling of such analog effects, this is just the fifth revision so enjoy.

The problems with modelling analog effects based on output only

One of the challenges that anyone who tries to model an
effect based on hardware or analog processes is that the digital world of audio
processing tends to be too perfect. Another problem is that specific algorithms
and techniques are not easily transposed into modern day desktop music/audio
production environments (or have little in the way of digital equivalents) or
aren't made readily available. Sometimes the artistic edge of sounds created
using imperfect or inferior technologies or mediums is a necessity. From my
own personal experience there is a huge divide in the area of electronic effects
such as the emulation of analog oscillators and filtersections, which often
sound so much more alive, far brighter and fuller in sound than a lot of attempts
to replicate them using entirely software based digital signal processing algorithms.

The Daleks

When the Daleks first appeared in 1963 a lot of the technology that modern
audio production facilities take for granted just weren't available to production
teams. The main piece of technology involved in the creation Dalek voices was
what is known as a ring modulator. A ring modulator works on the premise of
taking two audio sources that are involved in a process which takes the sum
and differences of the frequencies that are a part of the two audio sources
(and in the case of software a multiplication of signal content/frequencies
occurs). Typically a ring modulator may provide different types of wave to modulate
any input by (i.e. by a sine wave). Thus the two sound sources are defined as
the input (vocal) and the waveform that is being used to modulate it.

In the case of a ring modulator we typically talk about
modulating by the amplitude of waveforms (The amplitude being the 'height' part
of the wave). In the case of the Daleks the original setting was a modulation
frequency of 30hz. In the case of the Daleks created by BigFinish we are looking
at a modulation rate around double (November 02/2004, the guess of double the modulation rate has been proven right by information published at justyce.org from an interview with Alistair Lock, this does not mean all BF stories follow the pattern). However
there is a lot more to the sound unfortunately, and from another point of view
I suspect that if you looked at the output of the original ring modulator that
the modulating waveform i.e. a sine wave may in fact may NOT be perfect. Recreating
such malformed waveforms is probably near impossible as most digital equipment
and algorithms attempt to be extremely close to perfect (or attempt to makeup
for their inaccuracies). In the world of analog hardware not every sine wave
is perfect and there are unique flaws and design limitations to most pieces
of equipment that affect the output (of the equipment) as well.

The Degeneration of the Daleks

From listening to various recordings of Daleks it's not
hard to see that the effect employed has become far more complex and different
over time. On one end of the scale we have the first appearance of The Daleks
in 1963, then the final appearance of the Daleks on television (yes I'm sticking
with that fact) in "Remembrance of the Daleks" 1988. There is a stark
contrast between Dalek vocals produced in 1963 to those produced in 1988. Over
the years it appears that the settings employed to create them has changed;
at a guess this fact is primarily because the ring modulator used was most likely
utilized in many different programs (not just for vocal fx I'd imagine). The
other fact that made replication of the sound is that it appears that nobody
really bothered to write down how they did what and why; leading to all kinds
of issues and the appearance of quite aweful fx as heard on BBC trailers around
the time of the release of "The Mind of Evil" on VHS (1998). From
my own little investigations the following facts in regards to the sound probably
stand as being true/or at least perceptively so:

Daleks in 1963 were done very simply with little/next to
no pre or post production processing beyond the actual ring modulator

Daleks in "Genesis of the Daleks" & "Resurrection
of the Daleks" & "Revelation of the Daleks" have been extensively
post produced.

Daleks in "Remembrance of the Daleks" have more
in common with current off the shelf digital fx processing technology than any
other generation of Daleks since 1963. These Daleks were extensively pre &
post produced. There is no pitch shifting involved in creating this generation
of Dalek either, although they do seem to be rich in higher frequencies than
prior generations (I tend to call them "Happy" Daleks, as they are
spectrally speaking rather bright). I suspect this generation was based on the
effect as heard in such episodes as the William Hartnell era story "The
Chase" (1965), which would probably have been made available to the production
team at the time. Further these Daleks do not sound to me as if they were made
with the original ring modulator or if they are there was some kind of routing
and further processing involved, although I quite doubt it. I suspect this effect
was generated through a similar process to the Cybermen that appear in the 1988
adventure "The Silver Nemesis".

Genesis of the Daleks

Just a brief comment. The ringmodulator setting for this
lot would seem to be ~24hz. (Which just happens to be a similar setup as used
by JM&KH in their "Millenium of the Daleks" adventure).

Ressurection of the Daleks: A slightly closer look

After having a listen to the dialogue on my old beat up
copy of this serial it would seem some of my guesses about the effect used here
may well be true. The effect in Ressurection has departed quite significantly
from the original means of making the Dalek effect as it had been produced in
prior stories. It would appear that the production team had difficulties trying
to reproduce the irregularities of the original analog signal chain and modulation
source(s). Something extra had to be done and it appears some form of digital
distortion was used (perhaps in attempt to emulate the older effect, then giving
up on trying to achieve it and finding something pretty nice, or a happy accident
that allowed them to maybe 'modernize' the effect?) in conjunction with a ring
modulator (the original? Maybe not).

Remembrance of the Daleks: A more detailed look

Since coming into possesion of a retail copy of the original
videotape of this adventure (it's a good thing this isn't a review of the story
but rather the fx I think!) a number of things have become obvious. It seems
a somewhat different approach was taken in Remembrance to many other Dalek stories
in that the Dalek vocal fx seems to be all over the place in terms of settings
and modulation. There is very little consistency throughout the story in terms
to the Dalek vocals and how they were processed. This might make it sound as
if things were haphazardly thrown together, but in fact I believe the reason
this was done to emphasize the emotion and state of distress/operation of the
various Daleks even within the same "faction" (it may also be that
the people putting the program together got a tad lost at times considering
there is very little obvious difference between the factions bar the colour
variations). From my own observations at a guess this has led to Dalek vocals
with a huge difference in the modulation frequencies used, with an educated
guess that it switches between anywhere around ~10-30hz. So there goes the myth
of all Daleks being at 30hz with different pitch variations in the performances
of actors only doesn't it? Gee this article is starting to sound very fan boy
sad (are sound designers ever seen to be as sad?).

There
will be some sample files up with some contrast as soon as the author of this
article can get around to it/feels well enough to.

A short reminder for people who have made or intend to create Dalek like voice
fx

The Dalek Vocal effect is NOT achieved by flangering,
phasing and or pure pitch shifting. Those approaches tend to sound horrid and
incredibly amateurish. The 'silver buillet' solution: use a ring modulator.
30hz. Tweak. Not to mention try and sound like a Dalek.

Another terrible myth is that the signal modulation setting
on the ringmodulator should be set in excess of 100hz or multiples of 20-30hz,
this is not the case. Vocals become VERY difficult to discern at high multiples
in that range.

Examples Ahoy

An example file set can be downloaded here
(44.1khz 16bit Mp3 @ 128kbps ~382kb). This recording was recorded live and as
such hasn't been pre or heavily post edited. These samples are created by Owen
Spratley, they do not contain any samplings from the series or the Radiophonic
Workshop, BigFinish etc.

Coming Soon (some other far better sounding generations
of Dalek? Will it be Ressurection? Will it be Remembrance? May it be both? Maybe
it'll be the effect from the new series??? Only one of these options is pure fantasy).

Temporary Ressurectionesque
Example. I thought I might as well put up this not quite pristine example of
this effect, further more expressive vocals are required to demonstrate how
close it sounds to the read deal. Maybe not quite what you'd expect either...

What this article is not intended to be

The contents of this article are written out of interest
and fun. This text is not written in order to provide a one stop "show
me how to produce the originals" type article for quite a few reasons:

a) As every year passes by I discover more interesting and
more realistic ways to emulate the originals, and I'm not continually trying
to give out "ultimate answers", a Sound Designer in my mind is rather
like a magician, he/she has their own equipment and casts their spell upon an
audience. Said craft needs to be learned in order to appreciate what you're
really doing and why. For me there is also a certain level of heart that goes
into my sounds and I put my stamp on things, sound is a kind of expression.

b) The number of settings I personally use to create most
digital fx that I generate involve complex multi step procedures that tend to
involve a large number of parameters and variables that tend to involve educated
guesswork, dynamic change of settings etc, much of which is relative to recorded
signal, outputs, and the equipment used (I tend to buy & use a variety of
toys).

c) I'd like to see people learn & actually out do any
examples or effects that I use in any productions I am involved in.